1. Field Of The Invention
This invention generally relates to control systems for apparatuses and, in particular, to methods and control systems for controlling an apparatus having at least one machine function to be controlled in response to one or more operating parameters.
2. Statement Of The Prior Art
Control systems have long been widely used for a variety of apparatuses of which are included industrial, commercial and domestic machines and appliances. These machines and appliances each have at least one machine function and many have more. These functions are usually controlled in response to one or more operating parameters such as duration, position, temperature, and a wide variety of other generic and individual conditions. Many control systems have been developed for operating these machine functions in response to the various operating parameters and conditions. Included in these attempts are a number of circuits which employ digital electronics. In complex systems, where conditions permit, the control function is even handled by an appropriately programmed general purpose computer. In general, smaller, less complicated apparatuses have been restricted in the area of automated control to hard wired analog and digital control systems because the cost of the apparatuses will not usually justify the substantial cost of a general purpose computer. The disadvantages of such hard wired systems are that they are more costly to design and build, as they must be individually tailored for each application, and relatedly that they are more difficult systems in which to allow for variations in the various control functions. General purpose computers, on the other hand, are more easily adaptable to different variations as only the programs therefor need be changed. With the advent of large scale integration and, more specifically, the development of microcomputer chips, wherein entire small scale general purpose computers may be built into a single integrated circuit, it has been possible to produce the essence of individual general pupose computers on a large scale and thus low cost basis. As these integrated circuits are in fact general purpose computers, variations in different controlling parameters may be easily compensated for by means of the program contained therein.